The Constrained Single-Row Facility Layout Problem with Repairing Mechanisms

The single-row facility layout problem (SRFLP), which deals with the placement of some facilities along a row by minimizing the overall material flow cost among them, is usually studied as an unconstrained problem allowing the placement of the facilities arbitrarily without any restriction. But a practical SRFLP instance may require to respect certain constraints imposed on the arrangement of its facilities. Such an SRFLP model, which can be termed as a constrained SRFLP (cSRFLP), is studied here by requiring to place some facilities in fixed locations, and/or in predefined orders with/without allowing the arrangement of any other facility in between two ordered facilities. The handling of such a complex problem generally requires a specialized algorithm incorporating some problem-specific information for intelligent search. But the development of an algorithm needs expertise, from which practitioners often suffer. Hence, it is shown here how the cSRFLP can be tackled using a general-purpose algorithm with some repairing mechanisms outside the algorithm for forcibly satisfying the constraints of the problem. Employing a permutation-based genetic algorithm for this purpose, the potentiality of the proposed procedure is demonstrated by applying it to a set of cSRFLP instances of different sizes.